1974 series 2 4.2 difficult to start after 60 mile run

[mike020150]

Sadly, we all have days like that! First thoughts are that there may be a carb float issue. If the pumps could be heard running, a dodgy/sticking float or poorly set float level may be causing a very rich mixture which won't ignite easily. Try checking the condition of a plug to see if it's wet which might be another clue. Mike.

[alec2824]

I recently had a problem with my 4.2 xj6. Due to the Covid lockdown it had not been run for over a year and the fuel was suspect. I did llget it running but it was clearly running very rich and would stall at low revs. It appears that the AED was not shutting off causing excessive rich fuelling. The plugs were horribly sooted up. I disconnected the fuel supply to the AED, Blocked off the fuel pipe and the car runs well, and the spark plugs have lost their soot! Starting and running whilst cold is a touch tricky so I will need to "fix" the AED. Could I suggest you inspect your plugs to see the state of fuelling? Alec G.

[supersonic62]

Hi folks,
thanks Mike I have noted your advice about a dodgy/sticking float and to check the state of the plugs and will do so as soon as it turns a bit cooler as car is housed under a large carport with perspex roof and faces south so it`s like a greenhouse at the moment.That said the car is under a heavy duty car cover so avoids the sun. And to Alec G a question if I may , how would I go about disconnecting the fuel supply to the AED as in the fuel pipe is blocked off ? And like mike you suggest checking the condition of the plugs which I will do thanks for that, regards Paul

[supersonic62]

Hi folks, I am hoping to have a look at the problems mentioned previously in the next couple of days as going to be a bit cooler, so I will check the state of plugs and check the float in case stuck etc as advised by you good folk. But could someone please tell me how to disconnect the fuel supply to the AED and blocking off the fuel pipe, it might start and may show the refurbed AED which I had fitted could be faulty. Would I do this by clamping the fuel pipe to the AED ? I cannot find anything in the books regarding this.Trying to cover several issues while able. I know I did already ask this question but I do appreciate people have busy lives and can`t always give time to answer questions. I would like to think that after all the work that`s been done in the last little while that it`s nothing major but hey I wonder how many times that has been said before.These lovely old motor cars can be very challenging at times but I am determined to get it started ( with your help ) regards Paul

[mike020150]

From memory, the fuel feed to the AED is via a rubber hose. If so, release its jubilee clip, disconnect the rubber pipe and then, as a temporary measure, plug the end of the pipe with a suitably sized shanked bolt and retighten the jubilee clip to stop leaks. Carry out a similar exercise to block the rubber pipe from the AED to the T piece which feeds the AED air/fuel mixture into the carbs. This will avoid an excessively weak mixture. Then, you will be able to try running the engine having eliminated any effect of the AED. Mike.

[supersonic62]

Hi folks, I managed to have a go at trying to sort the beast and this is how I got on. Thanks to Mike for giving me details on how to disconnect the AED etc which I did after checking the plugs and floats .The plugs were the colour you would expect them to be in a normal running situation ( not wet with fuel or sooted up) so it seems no problem there, and the floats were ok as not stuck and would appear as you would expect to find them. But the devil still refused to start, so I put all back together. On the turn of the key the starter is spinning but the engine just will not fire up. I rang Marshall Jaguar in Peterborough,cambs just to see if they worked on the classics as I have receipts from them when the old chap used to take it there although that was a while back, and they said they didn`t as they don`t have the workshop manuals anymore. I think that just because you own a Jaguar these garages think you have a bottomless pit of money and yes it might seem I`m complaining but I am happy to pay if the car is sorted not just to get you home and not start again. It would be ideal if a mobile mechanic with the knowledge of these old motors exist somewhere, alas I don`t know of any . Two years ago I payed a mechanic that came recommended to me to travel from sussex to north cambs ( quite a distance) to replace the head gasket on my Rover 75 and that only lasted 900 miles and I had it done again locally. When you only have limited knowledge mechanically and apart from servicing etc you need the professionals it`s not easy with these lovely ( yes it`s still lovely ) old motors. Not quite sure where we go from here, Regards Paul

[mike020150]

If you still have the AED blocked off, it's likely to be difficult to start, especially if the carbs have been weakened off to compensate for an over-fuelling AED. Try using a can of Easystart. Give it a blast into the air intake and quickly try starting the engine. If it fires and runs briefly, you will know you have an adequate spark and vice versa. If it starts and continues to run, possibly with some misfiring, it's likely to be a fuel/carb tuning issue. Mike.

[3.8etypephil]

HI folks , my car dosen`t appear to have the oil safety cut off valve fitted , I have had a good look and can`t find it and on reading in the Jaguar workshop manual it says the valve was fitted to the later models of the series 2 and this was built in may 1974 and as we know the series 2 ran from 1973 onwards so I would class it as an early model as far as production went. I changed the AED for a replacement which I know was in full working order ( rare I know ) and car behaved the same so put original back and the oil pressure was consistant with where it should be.I started it up yesterday and it sat in the drive and idled for approx 30 minutes and ticked over perfectly all the gauges registering a healthy reading. I have checked all the wiring and connections to the ignition several times in case I have missed something as I have said on here before it was all replaced in April when I had the luminition system replaced along with coil, ballast resistor, dizzy cap, rotor arm, plugs etc. It has certainly foxed me, Regards Paul

I have just noticed this thread, so apologies for not having replied earlier; I recall that the majority of S2 XJ6s were fitted with the oil pressure safety cut off, so definitely worth a look; if fitted, it looks like an ordinary oil pressure switch (not the big one adjacent to the oil filter), and is located towards the lower rear on the left hand side of the cylinder block. If your car is so fitted, it can be bypassed by earthing the sender wire.
Failing that, PM me (do PMs work here?), or contact me via JagChat;- you're not too far from me, and I'd be happy to take a look if you're still struggling.

[supersonic62]

Hi folks ,
Thanks for advice given Mike it`s appreciated, will be trying that. And to Phil I have sent you a PM but not sure whether you received it or not as I submitted message but doesn`t register on the control panel that it has been sent, so hopefully you have it, regards Paul

[3.8etypephil]

Hi folks ,
Thanks for advice given Mike it`s appreciated, will be trying that. And to Phil I have sent you a PM but not sure whether you received it or not as I submitted message but doesn`t register on the control panel that it has been sent, so hopefully you have it, regards Paul

PMs are not working; I have nothing new, and the one I tried to send to you hasn't appeared in my out or sent boxes. I am reluctant to post my email or phone number on a public forum, so go via JagChat for contact.

[supersonic62]

Hi folks,
Just thought I would update you on the problems I was having with the old girl and where we are now. As you will no I have had problems over the last couple of years with the starting and the engine cutting out when warm ( which of course only takes a few minutes ) and refusing to start.And the start of this summer not even starting at all( despite only being driven 30miles back from a jaguar specialist last september and an eye watering bill and not being touched until this summer) .With members help and advice I had managed to check the most basics as limited knowledge allows and thinking surely after all this work done we are still no go .I did try Easy Start as Mike had suggested and it did fire for approx 5 seconds, so might not be as bad as once thought. But I was still at a loss as I really didn`t want to start stripping down already replaced items and be in a bigger pickle than before. Then 3.8etypephil saw my post and my ongoing saga with the old girl and said he would be happy to take a look if I was struggling as he wasn`t too far from me. And yes I sure was, Phil came to cambrigeshire an approx 85 mile round trip not once but twice in the last week. He checked the carbs, floats, AED, plugs and all the electrics and testing each as he moved along them.The car started, ran lumpy but was running ,Hallelujah ! ( no offence meant) it was running.Took it for a run Phil following behind in his XJR, something still amiss ( possibly newly fitted 2019 iluminition electronic ignition ? ).He returned six days later with the same enthusiasm as he`d had ( and in the mean time I had ordered another ballist resistor and coil to have as a spare) before and said he was wondering about the coil ( new one fitted with other items in 2019 and done approx 90miles). Phil changed the coil for the new one and we were in business, took the car for a run and runs just how it used to ( before 2018/19 issues began), I couldn`t stop grinning ! Phil set the carbs up as spec and the old girl was back on the road. Phil certainly knows these engines well along with many others of different marque`s and it as nice also to hear of some of his many cars he has owned and of the full life he has led. I would just like to say these issues that he worked through were not found in five minutes, people who work on their cars know it takes time to find issues and solve etc, and Phil gave several hours of his time to sorting the issues on my car and I can`t thank him enough.It`s a pity when we have to ( reluctantly ) visit a garage they don`t all have a motor engineer like Phil on the payroll, Regards Paul

[mike020150]

It's great to hear that the car is back running again and of the camaraderie involved. Well done Phil. Sharing the knowledge and helping one another are the basic building blocks of club life. Enjoy the sunshine! Mike.

[supersonic62]

Hi folks, just an update on the issues I had been having with the old girl, the journey that I and Phil had when the car was running as well as I had ever known was very short lived and the car struggled to start and keep running but never went on the road again . Covid and everyday life takes over and lockdown came and then the winter so no more progress was able to be made.So we hope for better things , if one can get the fuel ( due to the current crisis ) and if one can afford it ! I would like to think she will run again before we are forced off the road by the tree and bunny huggers. Even though she doesn`t run , she looks as nice as I always remember.We`ll see what this year brings who knows,regards Paul

[Andy P]

Hi Paul(supersonic62),
Glad your sticking with it and not throwing in the towel.
I'm sure you will be able to find and fix the problem eventually .
I used to have a 1974 Daimler Sovereign in the late 80's,wish I had kept that one. .
All the best and good luck with everything.
Take care.
Andy

[supersonic62]

Hi Andy, thanks for wishing me good luck with getting the ole girl sorted, we all grumble at times when things don`t go as we had hoped and no I couldn`t throw the towel in after seeing it for the first time 48 years ago this september when the old chap purchased her new ,and myself I have owned her 18 years this year, and it`s only done 51k so hardly run in lol. Phil the retired motor engineer said their`s not a lot wrong with that when he got it started last summer and he has worked on many Jaguars as well as other makes, time was against us then.So am optimistic about getting it going.I still feel myself it`s carb related and although they were rebuilt by a jaguar specialist( wont comment further) I am not certain if all or what of the gubbins were actually replaced.I contacted Burlen Ltd and gave them the engine number and ordered the needle and seat kit (wzx 1102) x2 and they are on back order so I will have those,I purchased 2 fuel inlet ball valves for HS8 2" SU Carbs and 2 stay up float kit`s (ethanol proof) as the front one gets stuck and we then have fuel from the overflow pipe so I am accumulating some bits that I may need. I have been watching repeats of minder from the seventies lately and watch how graceful the silver XJ6 looks and glides along the road with Arthur Daley at the wheel and what presence they had then , before many rotted away or ended up on the banger track, what sacrilege ! I know people say it`s lack of use and they may be right but I couldn`t take it out in the winter it just wouldn`t be right.This car replaced a 1963 Humber Super Snipe (quad headlamps) used through to the early seventies again the old chap never used it in the winter months and looked as good when he sold it as it did when first purchased, again plenty of leather and wood.Does she still exist reg XCT 10, green with smokey grey roof ( last change of owner 1994 according to DVLA) Well I have just had the renewal through for thee club so no doubt will be asking questions that only you knowledgeable folk can answer,Cheers Paul